Proteins that bind to IKKγ (NEMO) and down-regulate the activation of NF-κB

Inhibitor of kappa B kinase (IKK) gamma (IKK gamma), also referred to as nuclear factor kappa B (NF-kappa B) essential modulator (NEMO), is an important component of the IKK complex. Following the exposure of cells to NF-kappa B-inducing stimuli, the IKK complex catalyzes the phosphorylation of inhibitor of kappa B (I kappa B) proteins, which is a critical step that leads to the activation of NF-kappa B via the canonical pathway. The exact functions of IKK gamma as part of the IKK complex have not been fully elucidated. A number of proteins have been identified as directly interacting with IKK gamma and modulating the activity of the IKK complex. This mini review covers eight proteins that have been reported to bind to IKK gamma and lead to the suppression of the activities of the IKK complex and hence result in the down-regulation of the activation of NF-kappa B. The reported mechanisms by which these interactions suppress the activation of the IKK complex include the deubiquitination of IKK gamma and competition with upstream activators for binding to IKK gamma. (C) 2010 Elsevier Inc. All rights reserved.